Light emitting device

ABSTRACT

A light emitting device is constituted with a semiconductor light emitting element on which a support member is disposed on one surface provided with a p-side electrode and an n-side electrode and a fluorescent material layer is disposed on the other surface which is an opposite side of the one surface. The support member includes a resin layer, an electrode for p-side external connection and an electrode for n-side external connection disposed exposed at a surface opposite side of a surface where the resin layer is in touch with a light emitting element, and internal wirings disposed in the resin layer and electrically connecting between a p-side electrode and the electrode for p-side external connection respectively. The internal wirings include a metal wire and a metal plated layer, and a metal wire and a metal plated layer respectively connected in series.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No.2013-266464 filed on Dec. 25, 2013, and Japanese Patent Application No.2014-259029 filed on Dec. 22, 2014. The contents of these applicationsare incorporated herein by reference in their entirely.

BACKGROUND

1. Technical Field

The present disclosure relates to a light emitting device having asemiconductor light emitting element and a resin layer having an innerconductive member.

2. Background Art

Light emitting devices using a semiconductor light emitting element(light emitting element) such as a light emitting diode can be easilydownsized and can attain high luminous efficiency, which allows for theuse in wide range of applications. The light emitting devices using alight emitting element are roughly classified into two types: a face-uptype in which a light emitting element is provided with pad electrodeson a surface opposite side of the mounting substrate, and a face-downtype in which the electrodes are provided on a lower surface of a lightemitting element which faces the mounting substrate.

In the face-up type, the light emitting element is mounted on leadsetc., and the light emitting element and the leads are respectivelyconnected with a bonding wire or the like. Due to this configuration,when the light emitting element is mounted on the mounting substrate, ina plan view seen from a vertical direction to the surface of themounting substrate, a portion of the bonding wire is needed to be theouter side of the light emitting element, which limits the downsizing.

On the other hand, in the face-down type (which typically employs aflip-chip configuration), the pad electrodes disposed on the lightemitting element and the conductive pattern disposed on the mountingsubstrate can be electrically connected with the use of a connectingmeans such as bumps or metal pillars which are located on an inner sidethan the light emitting element in a plan view seen from a verticaldirection to the surface of the mounting substrate. This configurationallows downsizing of the light emitting device (particularly thedimensions in a plan view seen from a vertical direction to the mountingsurface of the mounting substrate), to a degree that is close to thesize of the light emitting element chip.

Recently, in order to facilitate further downsizing or to obtain furtherincrease in the luminous efficiency, the light emitting devices offace-down type have been used, in which respectively the growthsubstrate (light-transmissive substrate) such as a sapphire substratehas been removed, or the thickness of the growth substrate has beenreduced.

The growth substrate is used to allow growing an n-type semiconductorlayer and a p-type semiconductor layer which are constituent componentsof a light emitting element on its surface, and also has a function ofimproving the strength of the light emitting device by supporting thelight emitting element which has a small thickness and low mechanicalstrength. Thus, in a light emitting device in which after forming thelight emitting element, the growth substrate is removed or the thicknessof the growth substrate is reduced, for example, as shown in JP2010-141176A, a resin layer is provided at the electrode side (a sidefacing the mounting substrate) to support the light emitting element,and metal pillars which penetrate the resin layer are formed, andthrough the metal pillars, the electrodes of the light emitting elementand the conductive pattern disposed on the mounting substrate areelectrically connected. With such a resin layer which contains suchmetal pillars, the light emitting device can be secured with sufficientstrength.

On the other hand, although it is not a light emitting element, forexample, JP H05-299530A and JP 2008-251794A respectively describe amethod of using a metal wire, connecting a conductive pattern of amounting substrate and a terminal for external connection disposed on asurface of the resin layer.

RELATED ART DOCUMENT Patent Literature

See Patent Literature 1: JP 2010-141176A.

See Patent Literature 2: JP H05-299530A.

See Patent Literature 3: JP 2008-251794A.

In such a configuration described above, in order to provide sufficientstrength to the light emitting device, the resin layer may be needed tohave a sufficient thickness of, for example, several tens of micrometersor greater or 1 mm or greater. Accordingly, the metal pillars may alsobe needed to have a thickness of several tens of micrometers or greateror 1 mm or greater. On the other hand, the metal pillars as illustratedin JP 2010-141176A are generally formed by using electrolytic plating,which requires a long period of time to form such thick pillars (metallayers), which results in a decrease in mass productivity. Further, inthe case where a plated layer is formed thick, warpage is likely occurin the plated layer due to stress between the resin layer and the platedlayer and to internal stress within the plated layer. As a result,detachment of the plated layer from the light emitting element mayoccur, or manufacturing of the light emitting device with a constantlystable shape may not be able to achieve.

For this reason, in place of the metal pillars, metal wires may beconsidered to be used, with applying a method described in JPH05-299530A or JP 2008-251794A. With the thickness of the resin layerwithin such a range as described above, the inner conductive member canbe formed by simply changing the length of the metal wires, andsubstantially without changing the productivity.

On the other hand, light emitting elements are known to produce a largequantity of heat and their light-emitting output decrease with the risein temperature. For this reason, the heat generated in the lightemitting elements is needed to be quickly discharged to preventexcessive rise in the temperature. The thicker the resin layers of thesupport member, the longer metal wires are needed. However, generally,the metal wires are thinner than the metal pillars formed by using anelectrolytic plating, so that the longer the length of the metal layerthe greater the thermal resistance will be, resulting in a decrease ofthe heat dissipation performance through the metal wire as the heatconduction path. As a result, the emission output of the light emittingdevice decreases with an excessive rise in the temperature of the lightemitting element.

SUMMARY

Accordingly, an aim of the embodiments of the present disclosure is toprovide a light emitting device which has good balance between theproductivity and heat dissipation performance.

In order to solve the disadvantages described above, a light emittingdevice according to an embodiment of the present invention may include asemiconductor light emitting element, a resin layer, an electrode forp-side external connection, an electrode for n-side external connection,a p-side inner wiring, and an n-side inner wiring. The semiconductorlight emitting element may include a semiconductor stacked layer bodyconstituted with stacking a p-type semiconductor layer and an n-typesemiconductor layer and a p-side electrode electrically connected thep-type semiconductor layer and an n-side electrode electricallyconnected to the n-side electrode at one surface side of either asurfase side disposed with the p-type semiconductor layer or a surfaseside disposed with the n-type semiconductor layer of the semiconductorstacked layer. The resin layer is disposed on the one surface side ofthe semiconductor stacked layer body. The electrode for p-side externalconnection is disposed exposed on a surface of the resin layer and anelectrode for an n-side external connection is disposed exposed on asurface of the resin layer. The p-side inner conductive member isdisposed in the resin layer to electrically connect the p-side electrodeand the electrode for p-side external connection, and the n-side innerconductive member is disposed in the resin layer to electrically connectthe n-side electrode and the electrode for n-side external connection.The p-side inner conductive member and the n-side inner conductivemember respectively include a metal plating layer and a metal wire, or ametal plating layer and a metal wire bump.

In the light emitting device according to the embodiments of the presentinvention, a metal plated layer and a metal wire or a metal wire bumpare used in combination in the inner conductive members of the supportmember, thus, deformation of the metal plating layer can be suppressedand/or an increase in time of manufacturing can be controlled, and alsoan increase in the thermal resistance due to the metal wire or metalwire bump can also be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic perspective view illustrating a configuration ofa light emitting device according to a first embodiment of the presentinvention.

FIG. 1B is a schematic plan view illustrating a configuration of a lightemitting device according to a first embodiment of the presentinvention.

FIG. 1C is a schematic cross sectional view taken along line A-A of FIG.1B.

FIG. 1D is a schematic cross sectional view taken along line B-B of FIG.1B.

FIG. 2A is a schematic plan view illustrating a configuration of a lightemitting element according to a first embodiment of the presentinvention.

FIG. 2B is a schematic cross sectional view taken along line A-A of FIG.2A.

FIG. 3A is a schematic plan view illustrating another example of aconfiguration of a light emitting element according to a firstembodiment of the present invention.

FIG. 3B is a schematic cross sectional view taken along line A-A of FIG.3A.

FIG. 4A is a schematic cross sectional view taken along line B-B of FIG.3A.

FIG. 4B is a schematic cross sectional view taken along line C-C of FIG.3A.

FIG. 5 is a flowchart showing the flow of operations of manufacturing alight emitting device according to a first embodiment of the presentinvention.

FIG. 6A to FIG. 6D are each a schematic cross sectional view showing apart of a manufacturing operations of a light emitting device accordingto a first embodiment of the present invention.

FIG. 7A to FIG. 7D are each a schematic cross sectional view showing apart of a manufacturing operations of a light emitting device accordingto a first embodiment of the present invention.

FIG. 8A to FIG. 8D are each a schematic cross sectional view showing apart of a manufacturing operations of a light emitting device accordingto a first embodiment of the present invention.

FIG. 9A and FIG. 9B are each a schematic cross sectional view showing apart of a manufacturing operations of a light emitting device accordingto a first embodiment of the present invention.

FIG. 10A and FIG. 10B are each a schematic plan view illustrating aconfiguration of a light emitting device according to a secondembodiment and a third embodiment of the present invention respectively.

FIG. 11 is a flowchart showing the flow of operations of manufacturing alight emitting device according to a second embodiment of the presentinvention.

FIG. 12 is a flowchart showing the flow of operations of manufacturing alight emitting device according to a third embodiment of the presentinvention.

FIG. 13A is a schematic cross sectional view illustrating formation of astacked bump.

FIG. 13B is a schematic cross sectional view illustrating bonding of ametal wire.

FIG. 14A is a schematic plan view of a configuration of a light emittingdevice according to a fourth embodiment of the present invention.

FIG. 14B is a schematic cross sectional view taken along line A-A ofFIG. 14A.

FIG. 15A is a schematic cross sectional view taken along line B-B ofFIG. 14A.

FIG. 15B is a schematic cross sectional view taken along line C-C ofFIG. 14A.

FIG. 16 a flowchart showing the flow of operations of manufacturing alight emitting device according to a fourth embodiment of the presentinvention.

FIG. 17A is a schematic plan view illustrating formation of asemiconductor light emitting element in a manufacturing operationsaccording to a fourth embodiment of the present invention.

FIG. 17B is a schematic plan view illustrating formation of a firstresin layer in a manufacturing operations according to a fourthembodiment of the present invention.

FIG. 18A is a schematic plan view illustrating formation of a transversewiring layer in a manufacturing operations according to a fourthembodiment of the present invention.

FIG. 18B is a schematic plan view illustrating formation of a secondresin layer in a manufacturing operations according to a fourthembodiment of the present invention.

FIG. 19 is a schematic plan view illustrating formation of a third resinlayer in a manufacturing operation according to a fourth embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

A light emitting device and a method of manufacturing the light emittingdevice according to the embodiments of the present invention will bedescribed below. The drawings referred to in the description below areto schematically illustrate the embodiments, and the size, a space orinterval, locational relationship of the components may be exaggeratedor a portion of a component may not be shown. Also, the size and/orspace or interval of components may not be the same between a plan viewand its corresponding cross-sectional view. In the description below,the same designations or the same reference numerals denote the same orlike members and duplicative descriptions will be appropriately omitted.

In the light emitting device according to each embodiment of the presentinvention, a relative location expressed as “upper” and “lower”, “left”and “right” or so forth may be vice versa, depends on the situation. Inthe present specification, the terms such as “upper” and “lower” areused to illustrate a relative locational relationship between thecomponents in a drawing which is referred to, and unless specificallyindicated, are not intended to show absolute positional relationship.

First Embodiment Configuration of Light Emitting Device

With referring to FIG. 1A to FIG. 1D, a structure of a light emittingdevice according to a first embodiment will be described. A lightemitting device 100 according to the first embodiment is constitutedwith, as shown in FIG. 1A to FIG. 1D, a semiconductor light emittingelement 1 (hereinafter may be referred to as “light emitting element”)having an LED-(light emitting diode)-structure in which a growthsubstrate is removed, a support member 3 disposed on one surface side ofthe light emitting element 1, and a fluorescent material layer(wavelength converting layer) 2 disposed on other side of the lightemitting element 1. On the one surface side of the light emittingelement 1, an n-side electrode 13 and a p-side electrode 15 aredisposed, and through the metal wires 32 n, 32 p and the metal platedlayer 33 n, 33 p which serve as inner conductive members, the n-sideelectrode 13 and the p-side electrode 15 are connected to the electrodefor n-side external connection 34 n and the electrode for p-sideexternal connection 34 p, respectively. The light emitting device 100 isproduced in a wafer state, which is then singulated to obtain individuallight emitting devices 100, the detail of which will be described below.

Also, the light emitting device 100 of the present embodiment isconfigured to emit light whose wavelength has been converted by afluorescent material layer 2 which converts a portion of or the entireof the light emitted from the light emitting element 1 into light of adifferent wavelength, and emit the wavelength-converted light and lightemitted from the light emitting element 1. For example, with configuringso that the light emitting element 1 emits blue light and thefluorescent material layer 2 absorbs a portion of the blue light toconvert it in a yellow light, the light emitting device 100 can be awhite light source to emit white light made by mixing the blue light andthe yellow light. In the present embodiment and other embodiment to bedescribed below, the light emitting device 100 is provided with afluorescent material layer 2, but such a fluorescent material layer 2 isnot indispensable, and may not be employed.

In the present specification, as indicated with the coordinate axesshown in the appropriate drawings, for convenience of illustration, anormal direction of the surface provided with the n-side electrode 13and the p-side electrode 15 of the light emitting element 1 is indicatedas “+Z-axis direction” and “a plan view” is indicated as looking in thedirection from +Z-axis to −Z-axis. In the light emitting element 1 whichhas a rectangular shape in a plan view, the longitudinal direction isindicated as an x-axis direction and the lateral direction is indicatedas a y-axis direction. Also, the figures indicated as “cross sectional”each shows a cross section at a plane substantially perpendicular to anX-Y plane (a plane substantially in parallel to an X-Z plane or a Y-Zplane).

Next, the structure of the light emitting device 100 will be describedwith reference to the drawings. The light emitting element 1 has aplanar shape which is approximately rectangular in a plan view, and isan LED chip of a face-down type with the n-side electrode 13 and thep-side electrode 15 disposed on one surface side.

Example of Light Emitting Element

With referring to FIG. 2A and FIG. 2B, an example of light emittingelement 1 will be described in detail below. The light emitting element1 shown in FIG. 2A and FIG. 2B has a semiconductor stacked layer body 12in which an n-type semiconductor layer 12 n and a p-type semiconductorlayer 12 p are stacked. The semiconductor stacked layer body 12 isconfigured to emit light upon applying electric current between ann-side electrode 13 and a p-side electrode 15, and a light emittinglayer 12 a is preferably disposed between the n-type semiconductor layer12 n and the p-type semiconductor layer 12 p. Also, at one surface sideof a surface side disposed with the p-type semiconductor layer 12 p or asurface side disposed with the n-type semiconductor layer 12 n of thesemiconductor stacked layer 12, the p-side electrode 15 which iselectrically connected to the p-type semiconductor layer 12 p and then-side electrode 13 which is electrically connected to the n-typesemiconductor layer 12 n are provided. In the example shown in FIG. 2Aand FIG. 2B, the p-side electrode 15 and the n-side electrode 13 aredisposed at a side (the upper surface side in FIG. 2B) which is providedwith the p-type semiconductor layer 12 p of the semiconductor stackedlayer body 12.

The semiconductor stacked layer body 12 has at least one region in whichthe p-type semiconductor layer 12 p and the light emitting layer 12 aare absent, that is a region recessed from the surface of the p-typesemiconductor layer 12 p (hereinafter may be referred to as “stepportion 12 b” is formed. The floor of the step portion 12 b is anexposed surface of the n-type semiconductor layer 12 n and the n-sideelectrode 13 is disposed on the step portion 12 b. Also, a whole surfaceelectrode 14 is disposed on an approximately entire surface of the uppersurface of the p-type semiconductor layer 12 p. The whole surfaceelectrode 14 may be constituted with a reflecting electrode 14 a whichhas a good reflecting property and a cover electrode 14 b which coversentire of the upper surface and side surfaces of the reflectingelectrode 14 a. In addition, the p-side electrode 15 is disposed on aportion of the upper surface of the cover electrode 14 b. Also, thesurfaces of the semiconductor stacked layer body 12 and the wholesurface electrode 14 are covered with an insulating protective layer 16except the surfaces of the n-side electrode 13 and the p-side electrode15 which are the pad electrodes of the light emitting element 1.

Also, the semiconductor stacked layer body 12 can be made of a materialwhich is suitable to a semiconductor light emitting element, such asGaN, GaAs, AlGaN, InGaN, AlInGaO, GaP, SiC, or ZnO. In the presentembodiment, a portion of light emitted from the light emitting element 1is converted to light having a different wavelength by the fluorescentmaterial layer 2, so that a semiconductor stacked layer body 12 which isconfigured to emit light of a shorter wavelength such as blue light orgreen light is suitable.

For the n-type semiconductor layer 12 n, the light emitting layer 12 a,and the p-type semiconductor layer 12 p, a GaN-based compoundsemiconductor such as In_(X)Al_(Y)Ga_(1-X-Y)N (0≦X, 0≦Y, X+Y≦1) can besuitably used. Those semiconductor layers may respectively have asingle-layer structure, but have a stacked-layer structure, asuperlattice structure, or the like, which are made of layers ofdifferent compositions and thickness. Particularly, the light emitting12 a preferably has a single quantum well structure or a multiquantumwell structure which is made of stacked layer of thin layers each canproduce quantum effect.

In the case where a GaN-based compound semiconductor is used for thesemiconductor stacked layer body 12, the semiconductor layer can beformed on a growth substrate 11 (FIG. 6A) which is suitable for growinga crystal of a semiconductor layer, by using a known technique such as aMOCVD method (metal organic vapor phase epitaxy method), an HVPE method(hydride vapor phase epitaxy method), a MBE method (molecular beamepitaxy method). The thickness of the semiconductor layers are notspecifically limited and various thickness can be applied.

For the grows substrate for epitaxially growing the semiconductorstacked layer body 12, in the case where a semiconductor stacked layerbody 12 is formed by using nitride semiconductors such as GaN (galliumnitride) for example, an insulating substrate such as a sapphire with aprincipal plane being C-plane, R-plane, or A-plane, and a spinel(MgAl₂O₄); and silicon carbide (SiC), silicon, ZnS, ZnO, GaAs, anddiamond, and an oxide substrate such as lithium niobate and neodymiumgallate can be used.

In the present embodiment, during the manufacturing of the lightemitting device 100, the growth substrate is peeled off from thesemiconductor stacked layer body 12 to be removed. Thus, the lightemitting element 1 in a completed light emitting device 100 does notinclude a growth substrate. The lower surface of the semiconductorstacked layer body 12 from which the growth substrate has been removed,that is, the lower surface of the n-type semiconductor layer 12 npreferably has a recess-projection shape 12 c formed by roughtening thelower surface. With the recess-projection shape 12 c, the lightextraction efficiency of the surface can be improved. Such arecess-projection shape 12 c can be formed by performing wet etching onthe lower surface of the n-type semiconductor layer 12 n.

The whole surface electrode 14 serves as a current diffusion layer and areflecting layer and may be constituted with stacking a reflectingelectrode 14 a and a cover electrode 14 b. The reflecting electrode 14 ais disposed to cover an approximately entire surface of the uppersurface of the p-type semiconductor layer 12 p. Also, the cover layer 14b is disposed to cover entire of the upper surface and side surfaces ofthe reflecting electrode 14 a. The reflecting electrode 14 a is aconductive layer for dispersing electric current supplied through thecover electrode 14 b and the p-side electrode 15 disposed on a portionof the cover electrode 14 b to the entire surface of the p-typesemiconductor layer 12 p. Also, the reflecting electrode 14 a has a goodreflecting property and serves as a reflecting layer for reflecting thelight emitted from the light emitting element 1 toward the lightextracting surface. In the specification, the expression “havingreflecting property” refers to satisfactory reflecting light of thewavelength of emission of the light emitting element 1. Further, thereflecting electrode 14 a preferably has a reflecting property to lightof the wavelength which is converted by the fluorescent material layer2.

For the reflecting electrode 14 a, a metal material which has goodelectrical conductivity and good reflecting property can be used. Forthe metal material which has good reflecting property particularly in avisible region include Ag, Al or an alloy whose main component is one ormore of those metals can be suitably used. For the reflecting electrode14 a, a single layer or stacked layer of those metal materials can beemployed.

The cover electrode 14 b serves as a barrier layer for preventingmigration of the metal material which is a constituent of the reflectingelectrode 14 a. Particularly, in the case where Ag which easily migratesis used for the reflecting electrode 14 a, the cover electrode 14 b ispreferably provided. For the cover electrode 14 b, a metal materialwhich has good electrical conductivity and good barrier property can beused, and examples of such a metal material include Al, Ti, W, and Au.For the cover electrode 14 b, a single layer or stacked layer of thosemetal materials can be employed.

The n-side electrode 13 is disposed on the floor of the step portion 12b of the semiconductor stacked layer body 12 where the n-typesemiconductor layer 12 n is exposed. In addition, the p-side electrode15 is disposed on a portion of the upper surface of the cover electrode14 b. The n-side electrode 13 and the p-side electrode 15 are padelectrodes. The n-side electrode 31 is electrically connected to then-type nitride semiconductor layer 12 n, and the p-side electrode 33 iselectrically connected to the p-type nitride semiconductor layer 12 viaa whole surface electrode 14, to supply external electric current to thenitride semiconductor element 1. To the n-side electrode 13 and thep-side electrode 15, a metal wire 32 n and a metal wire 32 p which areinner conductive member in the supporting body 3 (FIG. 1A to FIG. 1D)are respectively connected.

Also, the example shown in FIGS. 2A and 2B, the p-side electrode 15 isconstituted with a stack of the pad electrode layer 15 a which isoriginally a pad electrode and an impact absorbing layer 15 b. Theimpact absorbing layer 15 b is not an essential component, but isemployed to reduce the impact at the time of wire bonding the metal wire32 p to reduce damage of the semiconductor stacked layer body 12. In theexample shown in FIGS. 2A and 2B, in the case where ball bonding isemployed for wire bonding as in the p-side electrode 15, the impactimposed on the bonding portion is relatively large. Therefore, theimpact absorbing layer 15 b is preferably provided. The n-side electrode13 may also be provided with an impact absorbing layer as in the p-sideelectrode 15. Also, without providing the p-side electrode 15, a portionof the whole surface electrode 14 may be used as a pad electrode and themetal wire 32 p may be directly connected to the whole surface electrode14.

A metal material can be used for the n-side electrode 13 and the padelectrode layer 15 a, and for example, a single metal member such as Ag,Al, Ni, Rh, Au, Cu, Ti, Pt, Pd, Mo, Cr or W, or an alloy whose maincomponent is one or more of those metals can be suitably used. In thecase where an alloy is used, for example as in an AlSiCu alloy, anonmetallic element such as Si may be contained as a compositionelement. For the n-side electrode 13 and the pad electrode 15 a, asingle layer or stacked layer of those metal material can be employed.The impact absorbing layer 15 b is provided to absorb impact at the timeof wire bonding for example, and a similar material as used for the padelectrode layer 15 a can also be used, but it is suitable to use amaterial which can establish good connection with the metal wire 32 p tobe connected on the upper surface of the impact absorbing layer 15 b. Inorder to absorb impact, the impact absorbing layer 15 b preferably has athickness of about 3 μm to 50 μm, more preferably about 20 μm to 30 μm.For example, in the case where the metal wire 32 p is made of Cu, it ispreferable that the impact absorbing layer 15 b is also employs Cu.

The protective layer 16 has an insulating property and covers the entireof the upper surface and the side surfaces of the light emitting element1 except for the connection parts of the n-side electrode 13 and thep-side electrode 15 to outside. The protective layer 16 serves as aprotective layer and an antistatic layer for the light emitting element1. In the case where a reflecting layer is disposed on the outside ofthe protective layer 16 which is disposed on the side surface portion ofthe semiconductor stacked layer structure body 12, the protective layer16 preferably has good light transmissive property to the light emittedfrom the light emitting element 1. Further, it is also preferable thatthe protective layer 16 has good light-transmissive property to light ofthe wavelength which is converted by the fluorescent material layer 2.For the protective layer 16, a metal oxide or a metal nitride can beused, for example, an oxide or a nitride of at least one elementselected from the group consisting of Si, Ti, Zr, Nb, Ta, and Al can besuitably used.

Also, for the protective layer 16, two or more types oflight-transmissive dielectric member with different refractive indicesmay be stacked to constitute a DBR (Distributed Bragg Reflector) layer.With the DBR layer, leaking light from the upper surface and the sidesurfaces of the light emitting element 1 can be reflected and returnedinto the light emitting element 1, so that the light extractionefficiency of the lower surface which is the light extracting surface ofthe light emitting element 1 can be improved. Examples of the DBR layerincludes a multilayer film in which a SiO₂ layer and a Nb₂O₅ layer arealternately stacked, in which, good reflectance can be obtained with amultilayer of at least three pairs or more, preferably seven pairs ormore.

Other Examples of Light Emitting Element

Next, with referring to FIG. 3A to FIG. 4B, other examples of lightemitting element will be described in detail. The same referencenumerals will be applied to the components which have the same orsimilar structure as those shown in FIGS. 2A and 2B and descriptionsthereof will be appropriately omitted.

The light emitting element 1A of another example shown in FIGS. 3A, 3B,4A, and 4B has a configuration in which the p-side electrode 15 which isthe p-side pad electrode is disposed extending on a portion of the uppersurface of the whole surface electrode 14, and the n-side electrode 13which is the n-side pad electrode is disposed, except for the regionwhere the p-side electrode is disposed and a portion close thereto, onapproximately entire of the upper surface and the side surfaces of thesemiconductor stacked layer body 12 via the protective layer 16. Thus,providing the n-side electrode 13 or the p-side electrode 15 on a widearea of the upper surface and the side surfaces of the light emittingelement 1A allows for conducting heat efficiently to the resin layer 31of the support member 3 to be described below, so that heat dissipationperformance can be improved. In the example shown in FIGS. 3A, 3B, 4A,and 4B, the n-side electrode 13 is disposed extending on a wide area ofthe upper surface and the side surfaces of the semiconductor stackedlayer body 12, but alternatively, the p-side electrode 15 may beprovided on a wide area. Also, both the n-side electrode 13 and thep-side electrode 15 may be disposed complementarily on a wide area. Forexample, in FIG. 3A, the p-side electrode 15 may be disposed on a widearea of a left half of the light emitting element 1A and the n-sideelectrode 13 may be disposed on a wide area of a right half of the lightemitting element 1A.

The n-side electrode 13 and/or the p-side electrode 15 may be disposedextending to the side surfaces of the semiconductor stacked layer body12 where the reflecting electrode 14 a is not provided, so as tofunction as a reflecting layer. With the DBR layer, leaking light fromthe upper surface and the side surfaces of the light emitting element 1can be reflected and returned into the semiconductor stacked layer body12, so that the light extraction efficiency of the lower surface whichis the light extracting surface of the light emitting element 1 can beimproved. In the case where the n-side electrode 13 and/or the p-sideelectrode 15 is used as a reflecting layer, a material having goodreflectivity is preferably used for at least a lower layer side(protective layer 16 side) of the electrode. Examples of the materialwhich has good reflecting property to visible light include Ag, Al or analloy whose main component is one or more of those metals.

In the light emitting element 1A, the step portion 12 b where the n-typesemiconductor layer 12 n is exposed is formed on the entire periphery ofthe semiconductor stacked layer body 12. Also, a whole surface electrode14 which is a stacked layer of the reflecting electrode 14 a and thecover electrodec 14 b is disposed on an approximately entire surface ofthe upper surface of the p-type semiconductor layer 12 p of thesemiconductor stacked layer body 12. Also, the surfaces of thesemiconductor stacked layer body 12 and the whole surface electrode 14are covered with an insulating protective layer 16 except for the entireof the lower surface of the semiconductor stacked layer 12, a portion ofthe floor of the step portion 12 b, and a portion of the upper surfaceof the whole surface electrode 14. also, in the light emitting element1A, in a similar manner as in the light emitting element 1, arecess-projection shape 12 c is formed on the entire surface of thelower surface of the n-type semiconductor layer 12 n.

Also, at the floor of the step portion 12 b, as shown in FIG. 3B andFIGS. 4A and 4B, the protective layer 16 has opening portions. That is,the opening portions are the regions where the n-type semiconductorlayer 12 n is not covered with the protective layer 16, and the openingportions serves the joining portions 13 a of the n-type semiconductorlayer 12 n and the n-side electrode 13. In the present example, as shownin FIG. 3A, the joining portion 13 a is disposed along the wholecircumference of the semiconductor stacked layer body 12. As describedabove, providing the joining portion 13 a in a wide area allows foruniform dispersion of the electric current which is supplied through then-side electrode into n-type semiconductor layer 12 n, so that theluminous efficiency can be improved.

Instead of forming the step portion 12 b around the entire periphery ofthe semiconductor stacked layer body 12, the step portion 12 b may beformed at a portion of the periphery. Reduction of the region to formthe step portion 12 b allows for increase of the area for the p-typesemiconductor layer 12 p and the light emitting layer 12 a, so that thelight emission quantity can be increased. Alternative to or in additionto the periphery, the step portion 12 b may be formed inner side of thesemiconductor stacked layer body 12 in a plan view. Forming the stepportion 12 b intermittently in a wide area rather than forming the stepportion in a part of the semiconductor stacked layer structure bodyallows for uniform dispersion of the electric current in the n-typesemiconductor layer as described above, without excessive increase ofthe step portion 12 b area. Instead of forming the step portion 12 baround the entire periphery of the semiconductor stacked layer body 12,the step portion 12 b may be formed at a portion of the periphery.

Also, in the light emitting device 100 (referring FIG. 1A to FIG. 1D) ofthe present embodiment, for convenience of illustration, a lightemitting element 1 is described as the light emitting element, but anyof the light emitting element 1 shown in FIGS. 2A and 2B, and the lightemitting element 1A shown in FIG. 3A to FIG. 4B can also be employed. Ina similar manner, in other embodiments to be described below, any of thelight emitting element 1 and the light emitting element 1A can beemployed.

Now returning to FIG. 1A to FIG. 1D, a structure of the light emittingdevice 100 will be described. The fluorescent material layer (wavelengthconverting layer) 2 absorbs a portion of or the entire portion of lightemitted from the light emitting element 1 and converts it to light of adifferent wavelength. The fluorescent material layer 2 can be formed ofa resin layer containing particles of a fluorescent material as awavelength converting material. The fluorescent material layer 2 may bedisposed, as shown in FIG. 1C, at a lower surface side of the n-typesemiconductor layer 12 n which is the light extracting surface of thelight emitting element 1 and which is provided with a recess-projectionshape 12 c (FIG. 2B).

The thickness of the fluorescent material layer 2 can be determinedaccording to the content of the fluorescent material, a desired colortone of mixed light of the light emitted from the light emitting element1 and the wavelength-converted light, and so forth. For example, thethickness of the fluorescent material layer 2 may be 1 to 500 μm, morepreferably 5 to 200 μm, and further preferably 10 to 100 μm,

The content of the fluorescent material in the fluorescent materiallayer 2, as a weight per unit volume, is preferably adjusted to 0.1 to50 mg/cm³. With the content of the fluorescent material in this rangeallows for sufficient color conversion.

A resin material having good light-transmissive property to lightemitted from the light emitting element 1 and the light whose wavelengthhas been converted by the fluorescent material layer 2 is preferablyused. Examples of such a resin material include a silicone resin, amodified silicone resin, an epoxy resin, a modified epoxy resin, a urearesin, a phenol resin, an acrylate resin, a urethane resin, afluororesin, or a hybrid resin containing one or more of those resins.

The fluorescent material (wavelength converting material) is notspecifically limited as long as it can be excited by the wavelength ofthe light emitted from the light emitting element 1 and emits light of adifferent wavelength than the wavelength of the exciting light, and agranular fluorescent material can be suitably employed. A granularfluorescent material has light scattering property and light reflectingproperty, so that it can serve as a light scattering member and thuslight diffusing effect can also be obtained. It is preferable that thefluorescent material is approximately uniformly mixed in the fluorescentlayer 2 which is also a resin layer. Also, two or more fluorescentmaterials may be uniformly mixed in the fluorescent material layer 2 ormay be distributed in a multilayer manner.

For the fluorescent material, a known material in the art can be used.Specific examples of the fluorescent materials include a YAG (yttriumaluminum garnet)-based fluorescent material activated with cerium, a LAG(lutetium aluminum garnet)-based fluorescent material activated withcerium, a nitrogen-containing calcium aluminosilicate(CaO—Al₂O₃—SiO₂)-based fluorescent material activated with europiumand/or chromium, a silicate ((Sr, Ba)₂SiO₄)-based fluorescent materialactivated with europium, β-sialon-based fluorescent material, a KSF(K₂SiF₆:Mn)-based fluorescent material. Also, a quantum dot phosphor canbe used.

Also, in order to add a light diffusing property to the fluorescentmaterial layer 2, an inorganic filler made of particles of a lighttransmissive inorganic compound, for example, an oxide, a carbonate, asulphate, or a nitride of a rare earth element such as Si, Al, Zn, Ca,Mg, and Y, or an element such as Zr, Ti, or a complex salt such asbentonite and potassium titanate may be added. The average particle sizeof such an inorganic filler may be similar to the average particle sizeof the fluorescent material described above.

The fluorescent material layer 2 can be formed by preparing a slurry inwhich a resin described above, particles of a fluorescent material, andother material such as an inorganic filler are contained in a solvent,applying the slurry on a lower surface of a semiconductor stacked layerbody 12 with the use of a spray method, a cast method, a potting methodor the like, then hardening the slurry applied. Also, the fluorescentmaterial layer 2 can be formed by separately preparing a resin platewhich contains particles of a fluorescent material and adhering theresin plate to a lower surface of the semiconductor stacked layer body12.

Also, the light emitting device 100 may be configured such that, withoutforming the fluorescent material layer 2, the lower surface of thesemiconductor stacked layer body 12 is designated to the lightextracting surface, so that the light emitted from the light emittingelement 1 can be directly discharged. Also, in place of the fluorescentmaterial layer 2, without containing a fluorescent material, a lighttransmissive resin layer may be disposed, or a light transmissive resinlayer which contains a light diffusing filler may be disposed.

The support member 3 has an approximately rectangular parallelepipedshape which in a plan view can contain the external shape of the lightemitting element 1, and is disposed to join the light emitting element 1at the surface side where the n-side electrode 13 and the p-sideelectrode 15 are disposed, and thus mechanically holds the lightemitting element 1 from which the growth substrate is removed. In a planview, the supporting member 3 has a shape approximately similar to theshape of the fluorescent material layer 2. The support member 3 includesa resin layer 31, electrodes for external connection (electrode forn-side external connection 34 n and electrode for p-side externalconnection 34 p) for mounting on a mounting substrate, and innerconductive members (metal wire 32 n, 32 p and metal plated layers 33 n,33 p) for electrically connecting an n-side electrode 13 and a p-sideelectrode 15 to corresponding external connection electrodesrespectively.

The resin layer 31 a base material of a reinforcing member of the lightemitting element 1. The resin layer 31 has an external shape, as shownin FIG. 1C and FIG. 1D, approximately similar to the external shape ofthe support member 3, and in a plan view, has an external shape whichcan contain the external shape of the light emitting element 1 and isapproximately similar to the external shape of the fluorescent materiallayer 2. Also, the resin layer 31 serves as a sealing resin layer whichseals the upper surface and the side surfaces of the light emittingelement 1. Thus, all the surfaces of the light emitting element 1 aresealed with the resin layer 31 and the fluorescent material layer 2which is a resin layer disposed on the lower surface side of the lightemitting element.

The resin layer 31 is, as shown in FIG. 1C and FIG. 1D, constituted withtwo stacked layers of a first resin layer (wire embedding layer) 311 inwhich metal wires 32 n, 32 p each penetrating in the thickness direction(the Z-axis direction) and a second resin layer (plated layer embeddinglayer) 312 in which metal plated layers 33 n, 33 p each penetrating inthe thickness direction are embedded. The first layer 311 and the secondresin layer 312 are well adhered to each other and integrated to formthe resin layer 31.

The resin material used for the first resin layer 311 and the secondresin layer 312 may be different, but it is preferable to use the samematerial to obtain better adhesiveness. For the resin materials of thefirst resin layer 311 and the second resin layer 312, the resinmaterials similar to those of the fluorescent material layer 2 can beused. In the case where the first resin layer 311 and the second resinlayer 312 are formed by way of compression molding, a raw material suchas EMC (epoxy mold compound) which is a powdery epoxy-based resin or SMC(silicone mold compound) which is a powdery silicone-based resin can besuitably used.

In order to enhance thermal conductivity, a heat conducting member maybe contained in the first resin layer 311 and the second resin layer312. With enhancing thermal conductivity of the first resin layer 311and the second resin layer 312, heat generated from the light emittingelement 1 can be quickly conducted and released to the outside. For thethermally conducting member, for example, granular carbon black or MN(aluminum nitride) can be used. In the case where the thermallyconducting member has electrically conducting property, the thermallyconducting member can be contained with a particle density in a range sothat the first resin layer 311 and the second resin layer 312 do notexhibit electrical conductivity.

For the first resin layer 311 and the second resin layer 312, a whiteresin made of a light transmissive resin material contained with areflecting filler may be used. With the use of a white resin at leastfor the first resin layer 311 which is joined to the upper surface ofthe light emitting element 1 so that the first resin layer 311 can serveas a light reflecting layer, leaking light from the upper surface andthe side surfaces of the light emitting element 1 can be reflected andreturned into the light emitting element 1, so that the light extractionefficiency of the lower surface which is the light extracting surface ofthe light emitting element 1 can be improved. In the case where thefirst resin layer 311 can serves as a light reflecting layer, the wholesurface electrode 14 of the light emitting element 1 may be formed witha light-transmissive material such as ITO (indium tin oxide) or IZO(indium zinc oxide).

A lower limit for the thickness of the resin layer 31 can be determinedso as to exhibit sufficient strength as a reinforcing member of thelight emitting element 1 from which the growth substrate has beenremoved, and an upper limit for the thickness of the resin layer 31 canbe determined in view of the thermal resistance of the inner conductivemembers made of the metal wires 32 n, 32 p and the metal plated layers33 n, 33 p, and productivity of the metal plated layers 33 n, 33 p. Forexample, in the case where the light emitting element 1 has an externalshape of about 1000 μm×500 μm in a plan view, the thickness of the resinlayer 31 can be 50 μm or greater. In view of thermal resistance of theinner wirings made of the metal wire 32 n, 32 p and the metal platinglayer 33 n, 33 p respectively, the thickness of the resin layer 31 ispreferably about 1000 μm or less, and more preferably about 250 μm orless.

The metal wire 32 n is disposed in the first resin layer 311 so as topenetrate in the thickness direction, and serves as an inner conductivemember which electrically connects the n-side electrode 13 and the metalplating layer 33 n. The metal wire 33 n is disposed in the second resinlayer 312 so as to penetrate in the thickness direction, and serves asan inner conductive member which electrically connects the metal wire 32n and the electrode for n-side external connection 34 n. That is, then-side electrode 13 of the light emitting element 1 is connected to theelectrode for n-side external connection 34 n by an inner conductivemember which is made of the metal wire 32 n and the metal plating layer33 n connected in series.

In a similar manner, the metal wire 32 p is disposed in the first resinlayer 311 so as to penetrate in the thickness direction, and serves asan inner conductive member which electrically connects the p-sideelectrode 15 and the metal plating layer 33 p. Also, the metal wire 33 pis disposed in the second resin layer 312 so as to penetrate in thethickness direction, and serves as an inner conductive member whichelectrically connects the metal wire 32 p and the electrode for p-sideexternal connection 34 p. That is, the p-side electrode 15 of the lightemitting element 1 is connected to the electrode for p-side externalconnection 34 p by an inner conductive member which is made of the metalwire 32 p and the metal plating layer 33 p connected in series.

For the metal wires 32 n, 33 p, a material having good electricconductivity and good thermal conductivity is preferably used, and forexample, Au, Cu, Al, or Ag, or an alloy whose main component is one ormore of those metals can be suitably used. Also, a metal wire providedwith a surface coating may be employed. In order to efficiently conductheat generated from the light emitting element 1, the diameter of thewire is preferably about 20 μm or greater, more preferably about 30 μmor greater, thus, the larger the diameter of the wire is the moreefficiently conducts the heat. The upper limit for the diameter of thewires is not specifically limited as long as the wire can be attached tothe n-side electrode 13 and the p-side electrode 15 of the lightemitting element 1, but preferably not to cause damage due to impactfrom the wire bonder experienced on the semiconductor stacked layer body12 at the time of wire bonding. Thus, for example, the diameter of thewire may be preferably about 3 mm or less, and more preferably about 1mm or less. In order to use a thicker wire at a lower price, a wire madeof Cu or Al, or an alloy whose main component is one or more of thosemetals can be suitably used. The shape of the wire is not specificallylimited, and in addition to the wires having a circular cross sectionalshape, a ribbon shaped wires with, for example, an elliptical or arectangular cross sectional shape may be used.

The wiring paths of the metal wires 32 n, 32 p are not specificallylimited, but are preferably arranged to penetrate in the thicknessdirection with a shortest path or an approximately shortest path,respectively. In view of the thermal resistance of the metal wires 32 n,32 p and the calorific value of the light emitting element 1, the lengthand the diameter of the metal wires 32 n, 32 p can be determined toprevent an excessive rise of the light emitting element 1.

Moreover, as in the present embodiment, with the use of the metal wires32 n, 32 p as the first layer of the inner conductive member, the wiringpath can be set with freedom, so that regardless of the positions of then-side electrode 13 and the p-side electrode 15 of the light emittingelement 1, connections with the n-side electrode 13 and the p-sideelectrode 15 can be easily established. Also, the distance between themetal layers 33 n, 33 p which is the second layer and the semiconductorstacked layer body 12 can be increased, so that effects of the internalstress from the metal plated layers 33 n, 33 p to the semiconductorstacked layer body 12 can be reduced. Accordingly, a risk of damage suchas generation of cracks in the semiconductor stacked layer body 12 canbe reduced.

As shown in FIG. 1C, the metal wire 32 p in the present embodiment isconnected to the p-side electrode 15 by wire bonding in a manner wherean end surface of the wire is connected to the p-side electrode havingan upper layer of an impact absorbing layer 15 b for absorbing impact atthe time of wire bonding. For this reason, a bump 32 a is formed at thetip of the metal wire 32 p which is the joining portion with the p-sideelectrode 15. The metal wire 32 n is connected to the n-side electrode13 by wedge bonding in a manner where a side surface of the end portionof the wire is connected to the n-side electrode. That is, the metalwire 32 n has a wedge-shaped end portion in one end and is connected tothe n-side electrode 13 with the wedge-shaped end portion. The exampleshown in FIG. 1C illustrate an example of connecting method of wire andthe method is not limited thereto. For example, at any electrodes,connection can be made by ball bonding, or made of wedge bonding.Further, the metal wire 32 p can be connected to the p-side electrode 15with the wedge-shaped tip portion formed at one end. Particularly,connecting with the use of wedge bonding, the metal wire 32 can bearranged in a curved state, so that the volume of metal present in theresin layer 31 can be increased. Accordingly, heat generated from thelight emitting element 1 can be further efficiently conducted.

The metal plated layers 33 n, 33 p can be formed by using anelectrolytic plating method, and a metal material having good electricalconductivity and good thermal conductivity is preferably used. Examplesof such a metal material include Cu, Au, Ni, and Pd. Of those, Cu, whichis an inexpensive and has relatively high electrical conductivity andthermal conductivity can be suitably used.

The metal plated layers 33 n, 33 p are preferably disposed so as to havebetter thermal conductivity than that of the metal wires 32 n, 32 p,thus, the two metal plated layers 33 n, 33 p are spaced apart from eachother to a degree no to create short circuit, and in a plan view,disposed in the second resin layer 312 with each area as large aspossible. Also, in the present example, the metal plated layers 33 n, 33p which are the inner conductive members respectively have a quadraticprism shape with an approximately square shape in a plan view, but theshape is not limited thereto, a columnar shape, a polygonal columnarshape, a truncated cone shape, a truncated pyramid shape, or the like,can be employed.

The metal plated layers 33 n, 33 p can be formed by using anelectrolytic plating with a thickness of about 50 to 150 μm through asingle electrolytic plating operation in a case of Cu. An increase ofthe thickness of the plated layer liable to cause warpage of the platedlayer due to the stress between the plated layer and the resin layerand/or to the internal stress. For this reason, the thickness of theplated layers 33 n, 33 p is preferably set to a thickness which can beobtained by plating operations of several times, or more preferably canbe obtained by a single set of plating operation. Thus, the thickness ofthe metal plated layers 33 n, 33 p is preferably set to about 50 to 200μm.

Also, the upper surface of the metal plated layers 33 n 33 p arearranged substantially in a same plane with the upper surface of thesecond resin layer 312. Then, the electrode for n-side externalconnection 34 n is disposed on the upper surface of the entire uppersurface of the metal plated layer 33 n and extending on a part of theupper surface of the second resin layer 312 which is adjacent to theupper surface of the metal plated layer 33 n. In a similar manner, theelectrode for p-side external connection 34 p is disposed on the uppersurface of the entire upper surface of the metal plated layer 33 p andextending on a part of the upper surface of the second resin layer 312which is adjacent to the upper surface of the metal plated layer 33 p.

The electrode for n-side external connection 34 n and the electrode forp-side external connection 34 p are pad electrodes for joining the lightemitting device 100 to an external mounting substrate. The electrode forn-side external connection 34 n and the electrode for p-side externalconnection 34 p are disposed on a surface of the resin layer 31 at anopposite side of the surface which is joined with the light emittingelement 1, that is, disposed on the upper surface of the resin layer 31.In the light emitting device 100, the upper surface side of the resinlayer 31 is designated to the mounting surface, and with the use of anelectrically conductive adhesive material such as a solder, theelectrode for n-side external connection 34 n and the electrode forp-side external connection 34 p are joined to respective wiring patternsof a mounting substrate. In the present embodiment, the surface providedwith the fluorescent material layer 2 serves as the light extractingsurface, so that the light emitting device 100 is provided with theelectrode for n-side external connection 34 n and the electrode forp-side external connection 34 p so as to be suitable for a top view typemounting.

For the electrode for n-side external connection 34 n and the electrodefor p-side external connection 34 p, in order to enhance joining with amounting substrate, for example, with the use of an Au alloy-basedjoining material such as Au—Sn eutectic solder, at least the uppermostlayers are preferably made of Au. For example, in the case where themetal plated layers 33 n, 33 p are made of a metal such as Cu or Alwhich is other than Au, in order to improve adhesion with Au, it ispreferable that thin layers of Ti and Ni are formed in this order byusing a sputtering method and an Au layer is formed stacked on the Nilayer. The electrode for n-side external connection 24 n and theelectrode for p-side external connection 34 p may have a total thicknessof about 0.1 μm to about 5 μm, more preferably about 0.5 μm to about 4μm.

In the case where the metal plated layers 33 n, 33 p are made of Au,without providing the electrode for n-side external connection 34 n andthe electrode for p-side external connection 34 p, the metal platedlayers 33 n, 33 p can be also designated to serve as the pad electrodesand their upper surfaces can be used for connecting surfaces to theoutside. Also, the electrode for n-side external connection 34 n and theelectrode for p-side external connection 34 p may be disposed on theentire or a part of the upper surface of the metal plated layers 33 n,33 p, and not to disposed on the upper surface of the second resin layer312, or the electrode for n-side external connection 34 n and theelectrode for p-side external connection 34 p may be disposed extendingonto the second resin layer 312, or further onto the side surfaces ofthe first resin layer 311. Disposing the electrode for n-side externalconnection 34 n and the electrode for p-side external connection 34 pextending onto the side surfaces of the resin layer 31 (in FIG. 1A toFIG. 1D, side surfaces in parallel to the X-Z plane, that is, in a planview, the side surfaces which include the longitudinal sides) allows thelight emitting device 100 to be mounted on a mounting substrate as aside-view type light emitting device.

Operation of Light Emitting Device

Next, the operation of the light emitting device 100 will be described.For convenience of illustration, the light emitting element 1 is assumedto emit blue light and the fluorescent material layer 2 is assumed toemit yellow light below.

In the light emitting device 100, upon connecting an external powersource between the electrode for n-side external connection 34 n and theelectrode for p-side external connection 34 p via a mounting substrate,through the metal plated layers 33 n, 33 p and the metal wires 32 n, 32p, electric current is supplied between the n-side electrode 13 and thep-side electrode 15 of the light emitting element 1. With the supply ofelectric current between the n-side electrode 13 and the p-sideelectrode 15, the light emitting layer 12 a of the light emittingelement 1 emits blue light.

The blue light emitted from the light emitting layer 12 a of the lightemitting element 1 propagates in the semiconductor stacked layerstructure body 12 and discharged from the lower surface of the lightemitting element 1. A portion of the discharged light is absorbed by thefluorescent material contained in the fluorescent material layer 2 andconverted into a yellow light, then extracted to outside. Also, aportion of the blue light is transmitted through the fluorescentmaterial layer 2 without absorbed by the fluorescent material, and thenextracted to outside. The light propagating downward in the lightemitting element 1 is reflected upward at the reflecting electrode 14 aand is emitted from the upper surface of the light emitting element 1.Then, the yellow light and the blue light extracted to outside of thelight emitting device 100 are mixed to produce a white light.

Method of Manufacturing Light Emitting Device

In the below, the light emitting device 1A will be described withreference to FIG. 5. As shown in FIG. 5, a method of manufacturing alight emitting device 100 includes, preparing light emitting element:S101, providing wiring: S102, forming first resin layer: S103, cuttingfirst resin layer: S104, forming plated layer: S105, forming secondresin layer: S106, cutting second resin layer: S107, disposing electrodefor external connection: S108, removing growth substrate: S109, formingfluorescent material layer (forming wavelength converting layer: S110,and singulating: S111, which are performed in this order. Now, withreference to FIG. 6A through FIG. 9B, (also, appropriately referring toFIG. 1A to FIG. 1D, FIGS. 2A and 2B, and FIG. 5), each operation will bedescribed in detail below. In each drawing of FIG. 6A to FIG. 9B, adetailed configuration of the light emitting element 1 (for example, aprotective layer 16 and a stacking structure of a semiconductor stackedlayer structure body 12) are omitted for ease of visualization. Also,the sizes and the arrangement relationships of other members may beappropriately simplified or exaggerated.

The preparing light emitting element: S101 includes preparing a lightemitting element 1 having a configuration shown in FIGS. 2A and 2B. Inthe preparing light emitting element S101 of the present embodiment, aplurality of the light emitting elements 1 are fabricated on a growthsubstrate 11 in a state of wafer where they are disposed in arrays. Ineach drawing of FIG. 6A to FIG. 9B, the coordinate axes indicate aZ-axis which is the up/down direction, an x-axis which is the right/leftdirection, and a Y-axis which is a direction perpendicular to a plane ofthe figure, as shown in FIG. 6A. Also, the “up” direction is indicatedas a +Z-axis direction. Each of FIG. 6A to FIG. 9B shows a crosssectional view taken along line A-A in the plan view shown in FIG. 1B.

More specifically, with the use of the materials described above, asemiconductor stacked layer body 12 is formed by stacking an n-typesemiconductor layer 12 n, a light emitting layer 12 a, and a p-typesemiconductor layer 12 p in this order on an upper surface of a growthsubstrate 11 made of sapphire or the like. Upon forming thesemiconductor stacked layer body 12, etching is carried out on a portionof the upper surface of the semiconductor stacked layer body 12 toremove the p-type semiconductor layer 12 p, the active layer, and aportion of the n-type semiconductor layer 12 n so as to create a stepportion 12 b in which the n-type semiconductor layer 12 n is exposed atthe floor.

At the same time of forming the step portion 12 b, etching may becarried out on the border regions of adjacent light emitting elements 1to expose the n-type semiconductor layer 12 n. Thus, in a lateroperation in the preparing light emitting element: S101, at least a sidesurface which includes the light emitting layer 12 a can be covered witha protective layer 16. Further, at the border regions, the semiconductorstacked layer body 12 may be entirely removed to expose the growthsubstrate 11. Thus, in the singulating: S111, dicing of thesemiconductor stacked layer body 12 becomes unnecessary, so thatsingulating can be performed easily by dicing only a layer made of aresin. In the example shown in FIG. 6A, the semiconductor stacked layerbody 12 in the border regions are completely removed.

Next, an n-side electrode 13 which serves as a pad electrode is disposedon the floor of the step portion 12 b. Also, on the region to serve asthe light emitting region which includes the p-type semiconductor layer12 p and the light emitting layer 12 a, a whole surface electrode 14constituted with a reflecting electrode 14 a covering approximatelyentire upper surface of the p-type semiconductor layer 12 p and a coverelectrode 14 b entirely covering the upper surface and the side surfacesof the reflecting electrode 14 a is disposed. In addition, the p-sideelectrode 15 which is a pad electrode is disposed on a portion of theupper surface of the cover electrode 14 b. Further, on the entire backsurface of the wafer except for the surfaces of the n-side electrode 13and the p-side electrode 15, for example, by way of sputtering and withthe use of an insulating material such as SiO₂, a protective layer 16 isformed. As described above, as shown in FIG. 6A, light emitting elements1 in a wafer state are fabricated.

Next, in the providing wiring: S102, as shown in FIG. 6B, with respectto each of the light emitting elements on the growth substrate 11, ametal wire 32 is provided using a wire bonder to connect the n-sideelectrode 13 b and the p-side electrode 15. The metal wire 32 is, asshown in FIG. 6B, connected to the p-side electrode 15 by way of ballbonding, a bump is formed at the tip of the metal wire 32, and isconnected to the n-side electrode by way of wedge bonding, and an end ofthe metal wire 32 is connected to the n-side electrode 13 with itswedge-shaped tip portion. At this time, a portion of the metal wire 32which is extending from the joining portion with the p-side electrode 15in a vertical direction or an approximately vertical direction isarranged with a length so that the wiring can be higher than apredetermined height. Here, the term “predetermined height” is referredto a height of the upper surface of the first resin layer 311 shown inFIG. 1C, which is a height of a virtual cutting line 41 shown by thebroken line in FIG. 6C.

Next, in the forming first resin layer: S103, as shown in FIG. 6C, byway of compression molding using a mold for example, the first resinlayer 311 is formed so as to completely enclose the light emittingelements 1 and the metal wires 32. At this time, the first resin layer311 is formed so that the upper surface of the first resin layer 311 isat least higher than the virtual cutting line 41.

Next, in the cutting first resin layer: S104, using a cutting machine,together with the metal wires 32, the first resin layer 311 is cut fromthe upper surface side to the thickness indicated by the virtual cuttingline 41. With this, each metal wire 32 is divided in two metal wires 32n, 32 p, and as shown in FIG. 6D, the cross section of the metal wires32 are exposed as the upper surfaces of the metal wires 32 n, 32 p whichare on the same plane with the upper surface of the first resin layer311.

Next, in the forming plated layer: S105, metal plated layers 33 n, 33 pare formed. In this operation, five sub-operations are included. A firstsub-operation includes forming seed layer in which a seed layer 33 a isformed on the entire upper surface of the wafer, that is on the entireupper surface of the first resin layer 311 and the entire upper surfaceof the metal wires 32 n, 32 p by stacking thin layers of Ni and Au inthis order by using a sputtering method. A second sub-operation includesforming plated layer in which by way of electrolytic plating method,using the seed layer 33 a as a plating current path, a plated layer 33 bis formed on the seed layer 33 a. FIG. 7A illustrates formation of theplated layer 33 b on the seed layer 33 a. The plated layer 33 b isformed so that the upper surface of the plated layer 33 b has a heightof at least a predetermined height. Here, the term “predeterminedheight” is referred to a height of the upper surface of the first resinlayer 312 shown in FIG. 1C, which is a height of a virtual cutting line42 shown by the broken line in FIG. 6C.

A third sub-operation includes forming resist pattern in which as shownin FIG. 7B, a resist pattern 61 is formed on the upper surface of theplated layer 33 b to cover the regions designated for the metal platedlayers 33 n, 33 p by using a photolithography method. A fourthsub-operation includes etching in which using the resist pattern 61 as amask, for example, by way of wet etching, the plated layer 33 b and thesheet layer 33 a are removed. Thus, as shown in FIG. 7C, the metalplated layer patterns 33 n, 33 p are formed A fifth sub-operationincludes removing resist pattern in which the resist pattern 61 isremoved by using ashing and a chemical treatment to complete the metalplated layers 33 n, 33 p. Since the seed layer 33 a is a sufficientlythin layer compared to the plated layer 33 b, in the specification, forconvenience of explanation, the seed layer 33 a and the plated layer 33b are collectively referred to as “metal plated layers 33 n, 33 p”.

In the etching in the fourth sub-operation, in the case where the platedlayer 33 b and the seed layer 33 a are etched by wet etching, etchingproceeds isotropically, not only in a thickness direction but also in atransverse direction. For this reason, the resist pattern 61 ispreferably formed widely so that the patterned metal plated layers 33 n,33 p obtained by the etching have predetermined intervals and sizes in aplan view, in consideration of the thicknesses of the plated layer 33 band the seed layer 33 a and the etching rate ratio between the thicknessdirection and the transverse direction.

Next, in the forming second resin layer: S106, as shown in FIG. 8A, byway of compression molding using a mold for example, the second resinlayer 312 is formed so as to enclose the metal plated layers 33 n, 33 p.At this time, the second resin layer 312 is formed so that the uppersurface of the second resin layer 312 is at least higher than thevirtual cutting line 42.

Next, in the cutting second resin layer: S107, using a cutting machine,together with the metal plated layers 33 n, 33 p which are containedtherein, the second resin layer 312 is cut from the upper surface sideto the thickness indicated by the virtual cutting line 42. With this, asshown in FIG. 8B, the upper surface of the metal plated layer 33 nconnected with the metal wire 32 n and the upper surface of the metalplated layer 33 p connected to the metal wire 32 b are exposed so as tobe in the same plane with the upper surface of the second resin layer312.

Next, in the disposing electrode for external connection: S108, as shownin FIG. 8C, the electrode for n-side external connection 34 n and theelectrode for p-side external connection 34 p are disposed on the uppersurface of the metal plated layers 33 n, 33 p and their adjacentportions of the upper surface of the second resin layer 312. Depositionof the metal layers to be served as the electrode for n-side externalconnection 34 n and the electrode for p-side external connection 34 pcan be achieved by sputtering. For example, in the case where the metalplated layers 33 n, 33 p are made of Cu, in order to obtain goodadhesion with an Au layer, it is preferable that a Ti layer and a Nilayer are formed in this order and then, the Au layer is stacked on theuppermost layer. For the patterning of the metal layer, a patterningmethod using etching or a patterning method using a lift-off operationcan be employed.

A patterning method using etching can be carried out as below. First,with the use of a sputtering method, a metal layer is formed on thewhole of the upper surface of the wafer, that is, on the whole of theupper surface of the metal plated layer 33 n, 33 p and the whole of theupper surface of the second resin layer 312. Next, with the use of aphotolithography method, a resist pattern which covers the regionsdesignated for the electrode for n-side external connection 34 n and theelectrode for p-side external connection 34 p is formed. Then, using theresist pattern as a mask, unnecessary portions of the metal layer areremoved by etching, and then, the resist pattern is removed.

A patterning method using lift-off operation can be carried out asbelow. First, with the use of a photolithography method, a resistpattern having openings corresponding to the regions designated for theelectrode for n-side external connection 34 n and the electrode forp-side external connection 34 p is formed. Next, with the use of asputtering method or the like, a metal layer is formed on the whole ofthe upper surface of the wafer. Then, the resist pattern is removed toremove the unnecessary portions of the metal layer on the resistpattern.

In the case where the electrode for n-side external connection 34 n andthe electrode for p-side external connection 34 p are not extended ontothe upper surface of the second resin layer 312 and formed only on theupper surfaces of the metal plated layers 33 n, 33 p, the electrode forn-side external connection 34 n and the electrode for p-side externalconnection 34 p can be formed by using an electrolytic plating method.

Next, in the removing growth substrate: S109, as shown in FIG. 8D, forexample, using an LLO (laser lift off) method, a chemical lift offmethod, or the like, the growth substrate 11 can be peeled and removed.At this time, the semiconductor stacked layer structure body 12 isreinforced by the support member 3 which has the resin layer 31 as itsbase material, so that damage such as cracks and splits can be avoided.

After the growth substrate 11 is peeled off, the exposed lower surfaceof the semiconductor stacked layer body 12 may be polished, and thenroughened, for example, by using a wet etching method, so that arecess-projection shape 12 c (FIG. 2B, FIG. 3B) may be formed. Bypolishing the surface, the growth substrate 11 which is peeled off canbe reused as a growth substrate 11 for growing a crystal of asemiconductor stacked layer body 12.

Next, in the forming fluorescent material layer (forming wavelengthconverting layer): S110, a fluorescent material layer 2 is formed on thelower surface side of the semiconductor stacked layer body 12. Thefluorescent material layer 2 can be formed, for example as describedabove, by spray coating of a slurry which contains a resin andfluorescent material particles in a solvent. In the preparing lightemitting element: S101, in the case where the semiconductor stackedlayer body 12 in the border region of adjacent light emitting elements 1is completely removes, the whole surfaces of the semiconductor stackedlayer body 12 are resin sealed with the fluorescent material layer 2which is made of a resin and the first resin layer 311.

Finally, in the singulating: S111, dicing is carried out along thevirtual cutting lines 43 set in the border regions among the lightemitting devices 100 to obtain the singulated light emitting devices100. In the preparing light emitting element: S101, in the case wherethe semiconductor stacked layer body 12 in the border regions ofadjacent light emitting elements 1 has been completely removed, theportions to be cut are made up solely of a resin layer, so that dicingcan be carried out easily. According to the operations described above,the light emitting device 100 shown in FIG. 1A to FIG. 1D can becompleted.

Also, as in the present embodiment, in the case where the support member3 is constituted with a stacked layer structure of the first resin layer(wire embedding layer) 311 and the second resin layer (plated layerembedding layer) 312, the wiring lengths of the metal wires 32 n, 32 pwhich are contained as the inner conductive members and the wiringlengths of the metal plated layers 33 n, 33 p can be determined with thethickness of each resin layer (the first resin layer 311 and the secondresin layer 312). Accordingly, variation in heat dissipation among thelight emitting devices 100 can be reduced. As a result, variation intemperature rise among the light emitting elements 1 can be reduced andthus variation in light emitting output due to temperature rise can bereduced. This effect can be obtained in a similar manner with differentorders of stacking or different numbers of stacking layers as in otherembodiments to be described below.

Second Embodiment Configuration of Light Emitting Device

Next, with reference to FIG. 10A, a light emitting device according to asecond embodiment and a third embodiment will be described. In the lightemitting device 100A according to the second embodiment shown in FIG.10A, the support member 3A includes, a resin layer 31A constituted withstacking layers in order from the light emitting element 1 side, a firstresin layer (plated layer embedding layer) 311A which contains metalplated layers 33 n, 33 p as its inner conductive members, and a secondresin layer (wire embedding layer) 312A which contains metal wires 32 n,32 p as its inner conductive members. That is, the light emitting device100A has a configuration in which the order of connection of the metalwires 32 n, 32 p and the metal plated layers 33 n, 33 p which are innerconductive members are reversed with respect to that of the lightemitting device 100 shown in FIG. 1A to FIG. 1D. Also, in the presentembodiment, as the light emitting element, the light emitting element 1Ashown in FIG. 3A to FIG. 4B is used, and the n-side electrode 13 and thep-side electrode 15 are respectively provided in a wide region of theupper surface side of the light emitting element 1A.

As in the present embodiment, in the case where the metal plated layers33 n, 33 p are used as the inner conductive member of the first layer,the metal plated layers 33 n, 33 p can be disposed in contact with awide region of the n-side electrode 13 and the p-side electrode 15respectively. Accordingly, heat dissipation performance through then-side electrode 13 and the p-side electrode 15 can be improved and thusthe temperature rise of the light emitting device 100 can be efficientlysuppressed. Particularly, in the light emitting element 1A shown in FIG.3A to FIG. 4B, in the case where the n-side electrode 13 and the p-sideelectrode 15 are disposed in a wide region of the upper surface side ofthe light emitting element 1A, and the metal plated layers 33 n, 33 pare disposed in contact with the n-side electrode 13 and the p-sideelectrode 15 respectively in a wide region, the n-side electrode 13 andthe p-side electrode 15 can be made with a substantially increasedthickness by the metal plated layers 33 n, 33 p. With this, the heatdissipating performance through the n-side electrode 13 and the p-sideelectrode 15 can be further improved and also diffusion of the currentin the n-side electrode 13 and the p-side electode 15 which are the padelectrodes can be improved.

Operation of Light Emitting Device

The light emitting device 100A according to the second embodiment has astructure which differs in the inner conductive member from the lightemitting device 100 according to the first embodiment. Therefore, uponconnecting an external power source between the electrode for n-sideexternal connection 34 n and the electrode for p-side externalconnection 34 p, and through the inner conductive member, the electriccurrent is supplied between the n-side electrode 13 and the p-sideelectrode 15 of the light emitting element 1, the operation of the lightemitting device 100A will be similar to that of the light emittingdevice 100, so that detailed description on the operation will beappropriately omitted.

Method of Manufacturing Light Emitting Device

Next, with reference to FIG. 11 (also, appropriately referring to FIG. 5and FIG. 10A), a method of manufacturing the light emitting device 100Aaccording to the second embodiment will be described. As shown in FIG.11, a method of manufacturing a light emitting device 100A includes,preparing light emitting element: S201, forming plated layer S202,forming first resin layer: S203, cutting first resin layer: S204,providing wiring: S205, forming second resin layer: S206, cutting secondresin layer: S207, disposing electrode for external connection : S208,removing growth substrate: S209, forming fluorescent material layer(forming wavelength converting layer: S210, and singulating: S211, whichare performed in this order.

First, in the preparing light emitting element: S201, in a similarmanner as in the preparing light emitting element: S101 in the firstembodiment, the light emitting elements 1A in a wafer state areprepared. The light emitting element 1A can be fabricated with a changein the region to form the step portion 12 b and a change in the regionin the upper surface of the protective layer 16 to where the n-sideelectrode 13 and the p-side electrode 15 are extended.

Next, in the forming plated layer: S205, metal plated layers 33 n, 33 pare formed with the procedure shown below. First, using aphotolithography method, a first resist pattern having openings inconformity to the upper surfaces of the n-side electrodes 13 and theupper surfaces of the p-side electrodes 15 is formed on the uppersurface of the wafer on which the light emitting elements are formed.Next, using a sputtering method, a seed layer is formed on the entireupper surface of the wafer. First, using a photolithography method, asecond resist pattern having openings corresponding to the regionsdesignated to form the metal plated layers 33 n, 33 p is formed. Thesecond resist pattern is formed with a thickness greater than thethicknesses of the metal plated layers 33 n, 33 p, to be formed. Next,using the seed layer as a current path, a plated layer if formed usingan electrolytic plating method. Then, removing the second resistpattern, that is, using a lift-off method, the plated layer ispatterned. At the same time, the first resist pattern is also removedalong with unnecessary portions of the seed layer. According to theprocedure described above, the metal plated layers 33 n, 33 p can beformed.

Next, in a similar manner as in the forming second resin layer: S106 andthe cutting second resin layer: S107, performing the forming first resinlayer: S203 and the cutting first resin layer: S204 to form the firstresin layer 311A so that the upper surfaces of the metal plated layers33 n, 33 p are exposed.

Next, in the providing wiring: S205, in a similar manner as in theproviding wiring: S102 in the first embodiment, using a wire bonder, ametal wire 32 (FIG. 6B) is arranged between the upper surface of themetal plated layer 33 n and the upper surface of the metal plated layer33 p. The metal wire 32 is connected to the upper surface of the metalplated layer 33 p by ball bonding. A bump is formed at the tip of themetal wire 32 and connected to the metal plated layer 33 n by wedgebonding. One end of the metal wire 32 has a wedge-shaped tip portionwhich is connected to the metal plated layer 33 n. Next, in a similarmanner as in the forming first resin layer: S103 and the cutting firstresin layer: S104 in the first embodiment, performing the forming secondresin layer: S206 and the cutting second resin layer: S207 to form thesecond resin layer 312A so that the upper surfaces of the metal wires 32n, 32 p are exposed.

Subsequent operations of the disposing electrodes for externalconnection: S208 to the singulating: S211 can be performed in a similarmanner as in the corresponding operations in the first embodiment andthe disposing electrodes for external connection: S108 to thesingulating: S111, so that detailed description will be omitted.According to the operations described above, the light emitting device100A shown in FIG. 10A can be completed.

Third Embodiment Configuration of Light Emitting Devise

Next, with reference to FIG. 10B, a light emitting device according to athird embodiment will be described. In the light emitting device 100Aaccording to the second embodiment shown in FIG. 10A, the support member3A includes, a resin layer 31A constituted with stacking layers in orderfrom the light emitting element 1 side, a first resin layer (platedlayer embedding layer) 311A which contains metal plated layers 33 n, 33p as its inner conductive members, and a second resin layer (wireembedding layer) 312A which contains metal wires 32 n, 32 p as its innerconductive members. That is, the light emitting device 100B has a resinlayer 31B made of three layers, that is, in addition to the metal wires32 n, 32 p and the metal plated layers 33 n, 33 p which provide theinner conductive members in the light emitting device 100, the resinlayer 31B further includes a third layer which contains the second metalwires 35 n, 35 p respectively connected to the inner conductive members.

Also, as a variation example of the third embodiment, a resin layer maybe made by stacking resin layers each containing metal plated layers,metal wires, or metal plated layers in this order from the lightemitting element 1 side. The number of the stacked layers is not limitedto two layers or three layers, but four layers or more can be employed.As described above, a thick resin layer can be formed by alternatelystacking the resin layer which contains a metal wire and the resin layerwhich contains the metal plated layer. At this time, controlling thethickness of a single metal layer allows for stacking of a plurality oflayers to obtain a thick resin layer while suppressing occurrence ofwarpage or peeling of the metal plated layer due to the stress. Also, inthe entire resin layer, the rate of the metal plated layer which hasgood thermal conductivity in the thickness is not reduced, so that athick support member having good heat dissipation performance can beformed.

Operation of Light Emitting Device

The light emitting device 100B according to the third embodiment has astructure which differs in the inner conductive member from the lightemitting device 100 according to the first embodiment. Therefore, uponconnecting an external power source between the electrode for n-sideexternal connection 34 n and the electrode for p-side externalconnection 34 p, and through the inner conductive member, the electriccurrent is supplied between the n-side electrode 13 and the p-sideelectrode 15 of the light emitting element 1, the operation of the lightemitting device 100B will be similar to that of the light emittingdevice 100, so that detailed description on the operation will beappropriately omitted.

Method of Manufacturing Light Emitting Device

Next, with reference to FIG. 12 (also, appropriately referring to FIG. 5and FIG. 10B), a method of manufacturing the light emitting device 100Baccording to the third embodiment will be described. As shown in FIG.12, a method of manufacturing a light emitting device 100B includes,preparing light emitting element: S301, providing wiring: S302, formingfirst resin layer: S303, cutting first resin layer: S304, disposingplating layer: S305, forming second resin layer: S306, cutting secondresin layer: S307, providing second wiring: S308, forming third resinlayer: S309, cutting third resin layer: S310, disposing electrode forexternal connection: S311, removing growth substrate: S312, formingfluorescent material layer (forming wavelength converting layer: S313,and singulating: S314, which are performed in this order.

The preparing light emitting element: S301 to the cutting second resinlayer: S307 are performed in a similar manner as in the preparing lightemitting element: S101 to the cutting second resin layer: S107 of thefirst embodiment respectively. Accordingly, a state which is shown inFIG. 8B, in which on each light emitting element 1, the first resinlayer 311 which contains the first metal wires 32 n, 32 p and the secondresin layer 312 which contains the metal plated layer 33 n, 33 p arestacked, and the upper surface of the metal plated layer 33 n, 33 p arerespectively exposed.

Next, in the disposing second wiring: S308, in a similar manner as inthe disposing wiring: S102 in the first embodiment, a wire bonder isused to provide a metal wiring between the upper surface of the metalplated layer 33 n and the upper surface of the metal plated layer 33 p.Next, in a similar manner as in the forming first resin layer: S103 andthe cutting first resin layer: S104, performing the forming third resinlayer: S309 and the cutting third resin layer: S310 to form the thirdresin layer 313 so that the upper surface of the second metal wire 35 n,35 p are exposed.

Subsequent operations of the disposing electrodes for externalconnection: S311 to the singulating: S314 can be perform in a similarmanner as in the corresponding operations in the first embodiment andthe disposing electrodes for external connection: S108 to thesingulating: S111, so that detailed description will be omitted.According to the operations described above, the light emitting device100B shown in FIG. 10B can be completed.

Variant Example

Next, with reference to FIG. 13, a variant example of providing wiring(providing wiring: S102, providing wiring: S205, providing first wiring:S302 and providing second wiring: S308) will be described.

In the embodiments described above, at the time of providing metal wires32 n, 32 p, 35 n, and 35 p, (hereinafter may be referred to as “metalwire 32”) using a wire bonder, the metal wire 32 is arranged between then-side electrode 13 and the p-side electrode 15, or between the metalplated layer 33 n and the metal plated layer 33 p. As shown in FIG. 13B,an end portion of the metal wire 32 is fusion bonded to the n-sideelectrode 13 etc. by ball bonding in which, using the wire bonder 50, anend portion of the metal wire 32 is pressed on the upper surface of then-side electrode 13 or the like while applying ultrasonic vibrations. Atthis time, a ball-shaped bump 32 a which is larger than the diameter ofthe metal wire 32 is created at the fusion-bonded portion.

In the present variant example, in place of the metal wire 32, a stackedbump 32A which is a stack of bumps 32 a as shown in FIG. 13A is used forthe inner conductive member. As described above, the stacked bump 32A isformed thicker than the original wire 32. Accordingly, with the use ofthe stacked bump 32A, the thermal resistance of the inner conductivemember is reduced compared to the case that employs the metal wire 32,thus, heat dissipation performance of the light emitting device 100etc., can be improved. In the present variant example, the stacked bump32A is used for the inner conductive member, but it is not limitedthereto, in place of the stacked bump 32A, the inner conductive membermay be constituted with a single bump 32 a. Also, in the presentspecification, inner conductive elements constituted with a stacked bump32A inclusive of a plurality of bumps 32 a and inner conductive elementsconstituted with a single bump may be collectively referred to as “metalwire bump”. The expression “stacking number of one” in the presentspecification does not include a configuration in which a bump is formedat a tip of the metal wire as in the first embodiment, but refers to aconfiguration which includes only a bump which is substantially thickerthan the metal wire.

The stacked bump 32A can be made by, using a wire bonder 50,repetitively performing forming a bump 32 a and cutting metal wire 32 atupper end of the bump 32 a. The stacked bump 32A is formed to have alarger diameter compared to the diameter of the metal wire 32, and tohave sufficient rigidity so as not to fall off at the time of formingfirst resin layer 311 and the like. Thus, wiring in a substantiallysquare shape or a reverse U-shape between two electrodes is not needed.Accordingly, in the present variant example, in the providing wiring,stacked bumps 32A are formed on the upper surface of each n-sideelectrode 13 etc., with at least a predetermined height (i.e. equal orgreater than the thickness of the first resin layer 311 etc., whichincorporates the stacked bump 32A at the time of completion of the lightemitting device 100 etc.). The subsequent operations of forming thefirst resin layer 311 etc. and cutting the first resin layer 311 can beperformed in a similar manner as in the case where a metal wire 32 isused as the inner conductive member.

Fourth Embodiment Configuration of Light Emitting Device

With referring to FIG. 14A to FIG. 15B, and FIG. 17A to FIG. 19, a lightemitting device according to a fourth embodiment will be described. Inthe light emitting device 100C according to the fourth embodiment shownin FIG. 14A to FIG. 15B, the support member 3C includes a resin layer31C constituted with stacked layer, in order from the light emittingelement 1C side, a first resin layer (plated layer embedding layer) 311Cwhich contains metal plated layers 33 n, 33 p as its inner conductivemembers, a second resin layer (wire embedded layer) 312C in which innerconductive members of stacked bumps 32An, 32Ap and transverse wiringlayers 36 n, 36 p are embedded, and a third resin layer (plated layerembedding layer) 313C in which second metal plated layers 37 n, 37 p areembedded as an inner conductive members. Also, on the upper surface ofthe third resin layer 313C which is the uppermost layer, upper surfacesof the second metal plated layers 37 n, 37 p are exposed so as to be ina same plane as the upper surface of the third resin layer 313C. In thepresent embodiment, the exposed upper surfaces of the second metalplated layers 37 n, 37 p also serve as the electrodes for externalconnection.

As shown in FIG. 14A, in the present embodiment, the light emittingelement 1C is arranged with four p-side electrodes 15 each having alengthwise long rectangular shape in a plan view, and between eachadjacent two p-side electrodes 15 of the four, two n-side electrodes 13having a circular shape in a plan view are arranged in a longitudinaldirections, thus, in total of six n-side electrodes 13 are arranged. Inthe light emitting element 1C, in addition to the configuration of thelight emitting element 1 as shown in FIG. 2A and FIG. 2B, the stepportion 12 b is formed in a plurality of locations. The n-side electrode13 is provided at each step portion 12 b and also the p-side electrodes15 are provided at a plurality of locations. Thus, the dissipation ofthe current supplied from outside can be improved. The light emittingelement 1C is configured in a similar manner as in the light emittingelement 1 except that the number of the electrodes is increased. Thus,detailed description of the light emitting element 1C will beappropriately omitted.

The first resin layer 311C is disposed at the upper surface side of thelight emitting element 1C, to support the inner conductive member of sixfirst metal plated layers 33 n (FIG. 17B) electrically connected to then-side electrodes 13 respectively and four first metal plated layers 33p (FIG. 17B) electrically connected to the p-side electrodes 15respectively, while sealing the upper surface and the side surfaces ofthe light emitting element 1C. Also, the first resin layer 311C is incontact with the fluorescent material layer 2 at an outer side of theouter peripheral portion of the light emitting element 1C. Thus, theentire surfaces of the light emitting element 1C are resin-sealed withthe first resin layer 311 and the fluorescent material layer 2.

As for the first metal plated layer 33 n, as shown in FIG. 17B, onefirst metal plated layer 33 n is disposed on each upper surface of thesix n-side electrodes 13, and as shown in FIG. 18A, the upper surfacesof the first metal plated layers 33 n are connected to one transversewiring layer 36 n. The first metal plated layer 33 n is a columnar metallayer with a circular shape in a plan view. As for the first metalplated layer 33 p, as shown in FIG. 17B, one first metal plated layer 33n is disposed on each upper surface of the four p-side electrodes 15,and as shown in FIG. 18A, the upper surfaces of the first metal platedlayers 33 p are connected to one transverse wiring layer 36 p. The firstmetal plated layer 33 p is a quadrangular prism-shaped metal layer witha lengthwise long rectangular shape in a plan view.

The second resin layer 312C is formed in contact with the upper surfaceof the first resin layer 311C and incorporates the inner conductivemembers each made of a transverse wiring 36, 36 p and a stacked bump32An, 32Ap respectively. The transverse wiring layer 36 n and thetransverse wiring layer 36 p are as shown in FIG. 18A, in a plan view,formed in a comb-shape each having three teeth and four teeth, which arerespectively extended in a vertical direction (a Y-axis direction) andengage with each other. The transverse wiring 36 n and the transversewiring 36 p are spaced apart from each other so as not to cause a shortcircuit. The transverse wirings 36 n, 36 p can be formed by using ametal material which is similar to that in the lower layer of the firstplating layers 33 n, 33 p, or by using a metal material which has goodbonding property, and using sputtering method or the like.

The transverse wiring layer 36 n is, as shown in FIG. 18A, connected tosix first metal plated layers 33 n at its lower surface side and asshown in FIG. 18B, connected to nine stacked bumps 32An at its uppersurface side. The transverse wiring layer 36 n is, as shown in FIG. 18A,connected to four first metal plated layers 33 p at its lower surfaceside and as shown in FIG. 18B, connected to twelve stacked bumps 32Ap atits upper surface side.

A comparison between FIG. 18A and FIG. 18B indicates that, in a planview, some of the first metal plated layers 33 n which are the n-sideinner conductive member at a lower layer side are not overlapped withany one of the stacked bumps 32An which are the n-side inner conductivemember at an upper surface side. For this reason, through the transversewiring layer 36 n which is provided extending in a lateral direction(X-Y plane), the first metal plated layer 33 n and the stacked bump 32Arare configures to be electrically connected.

A comparison between FIG. 18A and FIG. 18B indicates that, in a planview, some of the first metal plated layers 33 p which are the p-sideinner conductive member at a lower layer side are overlapped with someof the stacked bumps 32Ap which are the p-side inner conductive memberat an upper surface side. For this reason, through the transverse wiringlayer 36 n which is provided extending in a lateral direction (X-Yplane), the first metal plated layer 33 n and the stacked bump 32Ar areconfigures to be electrically connected. This allows a configuration inwhich the first metal plated layers 33 p and the stacked bumps 32Ap arenot overlapped in a plan view.

In a plan view, nine stacked bumps 32An are arranged as shown in FIG.18B, on the transverse wirings 36 n, and as shown in FIG. 19, in aregion overlapping with the second metal plated layer 37 n which is anelectrode for n-side external wiring at the upper surface side. Also, ina plan view, twelve stacked bumps 32Ap are arranged as shown in FIG.18B, on the transverse wirings 36 p, and as shown in FIG. 19, in aregion overlapping with the second metal plated layer 37 p which is anelectrode for p-side external wiring at the upper surface side.

The third resin layer 313C is disposed in contact with the upper surfaceof the second resin layer 312C and incorporates the inner conductivemembers each made of the second metal plated layer 37 n, 37 p. Uppersurfaces of the second metal plated layer 37 n and the second metalplated layer 37 p are exposed from the third resin layer 313C, andrespectively also serves as the electrode for n-side external connectionand the electrode for p-side external connection. Also, the second metalplated layer 37 n has nine stacked bumps 32An connected to its lowersurface side, and the second metal plated layer 37 p has twelve stackedbumps 32An connected to its lower surface side.

It is preferable that in the second metal plated layers 37 n, 37 p, atleast the uppermost layer is made of Au or an alloy whose majorcomponent is Au. Alternatively, without using the second metal platedlayers 37 n, 37 p also as the electrodes for external connection,electrodes for external connection can be provided separately on theupper surface of the second metal plated layers 37 n, 37 p.

As described above, a plurality of (i.e. six) n-side electrodes 13 areconnected to the single second metal plated layer 37 n which also servesas the electrode for external connection, by the first metal platedlayer 33 n, the transverse wiring layer 36 n, and the stacked bump 32Anwhich form an n-side inner conductive member. Also, a plurality of (i.e.four) p-side electrodes 15 are connected to the single second metalplated layer 37 p which also serves as the electrode for externalconnection, by the first metal plated layer 33 p, the transverse wiringlayer 36 p, and the stacked bump 32Ap which form an p-side innerconductive member.

As described above, in a plan view, the second metal plated layer 37 nwhich is the electrode for n-side external connection is disposed in aregion which is an upper half (+y-axis direction side), and the secondmetal plated layer 37 p which is the electrode for p-side externalconnection is disposed in a region which is a lower half (-Y-axisdirection side). For this reason, it is not possible to stacking innerconductive member in a direction directly upward of the n-side electrode13 and the p-side electrode 15 and respectively connected to the secondmetal plated layer 37 n and the second metal plated layer 37 p.

In the present embodiment, the inner conductive member is made of threelayer structure and interposing the transverse wirings 36 n, 36 p.Accordingly, a plurality of electrodes of at either the n-side or p-sideof the light emitting element 1C can be connected to the second platedlayers 37 n, 37 p which are a pair of electrodes for external connectiondemarcated in two simple rectangular regions. That is, with the internalelectrode having a multilayer structure, even in the case where the padelectrodes of the light emitting elements are disposed with acomplicated arrangement, connection with the electrodes for externalconnection which have simple structures can be achieved. Theconfiguration of the inner conductive member s is not specificallylimited to those illustrated in FIG. 3A to FIG. 4B, and for example, inplace of the stacked bumps 32An, 32Ap, metal wires 32 (for example, FIG.13B) may be employed.

Operation of Light Emitting Device

The light emitting device 100C according to the fourth embodiment has astructure which differs in the inner conductive member from the lightemitting device 100 according to the first embodiment. Therefore, uponconnecting an external power source between the electrode for n-sideexternal connection 37 n and the electrode for p-side externalconnection 37 p, and through the inner conductive member, the electriccurrent is supplied between the n-side electrode 13 and the p-sideelectrode 15 of the light emitting element 1C, the operation of thelight emitting device 100C will be similar to that of the light emittingdevice 100, so that detailed description on the operation will beappropriately omitted.

Method of Manufacturing Light Emitting Device

Next, with reference to FIG. 16 (also, appropriately referring to FIG.14A to FIG. 15B), a method of manufacturing the light emitting device100C according to the fourth embodiment will be described. As shown inFIG. 16, a method of manufacturing a light emitting device 100 includes,preparing light emitting element: S401, forming first plated layer:S402, forming first resin layer: S403, cutting first resin layer: S404,forming transverse wiring: S405, forming wire bump: S406, forming secondresin layer: S407, cutting second resin layer: S108, forming secondplated layer: S409, Forming third resin layer: S410, cutting third resinlayer : S411, removing growth substrate: S412, forming fluorescentmaterial layer (forming wavelength converting layer): S413, andsingulating: S414, which are performed in this order.

In the below, with reference to FIG. 17A to FIG. 19, (also FIG. 2A toFIG. 16 when appropriate), each operation of a method of manufacturingthe light emitting device 100C will be described. In FIG. 17A to FIG.19, manufacturing of single light emitting device 100C is illustrated,but until singuraled in singulation: S414, the light emitting devices100C are produced in a wafer state where a plurality of light emittingelements 1C are arranged.

First, in preparing light emitting element: S401, in a similar manner asin preparing light emitting element: S101 in the first embodiment, asshown in FIG. 17A a wafer having arrays of light emitting elements 1Cdisposed on a growth substrate 11 is prepared. On the upper surface ofeach light emitting element, six n-side electrodes 13 and four p-sideelectrodes 15 are formed.

Next, in a similar manner as in the forming plated layer: S202, theforming first resin layer: S203 and the cutting first resin layer: S204,respectively of the second embodiment, forming first plated layer: S402,forming first resin layer: S403 and cutting first resin layer: S404, areperformed, to form the first resin layer 311C which incorporates thefirst metal plated layers 33 n, 33 p and expose the upper surfaces ofthose. On each of the n-side electrodes 13, single first metal platedlayer 33 n is formed, and on each of the p-side electrodes 15, singlefirst metal plated layer 33 p is formed,

Next, in the forming transverse wiring layer: S406, using a sputteringmethod or the like, as shown in FIG. 18A, transverse wiring layers 36 n,36 b are formed on the upper surface of the first resin layer 311C. Forthe patterning of the transverse wiring layers 36 n, 36 p, a patterningmethod using etching or a patterning method using a lift-off operationcan be employed. Next, in the forming wire bump: S406, using a wirebonder, as shown in FIG. 18B, stacked bumps 32An, 32Ap are formed on therespective predetermined positions of the transverse wiring layers 36 n,36 p. At this time, the upper surfaces of the stacked bumps 32An, 32Apare formed with a same height as or higher than the height of the uppersurface of the completed second resin layer 31C.

Next, in a similar manner as in the forming second resin layer: S106 andthe cutting second resin layer: S107, of the first embodiment, formingsecond resin layer: S407 and cutting third resin layer: S408 areperformed. Thus, as shown in FIG. 18B, a second resin layer 312C whichincorporates transverse wiring layers 36 n, 36 p and stacked bumps 32An,32Ap, and exposes the upper surfaces of the stacked bumps 32An, 32Ap isformed.

Next, in a similar manner as in the forming second plated layer: S105,the forming second resin layer: S106 and the cutting second resin layer:S107 respectively of the first embodiment, forming second plated layer:S409, forming third resin layer: S410, and cutting third resin layer:S411 are performed. Thus, on the second resin layer 312C, as shown inFIG. 19, a third resin layer 313C which incorporates a second metalplated layers 37 n, 37 p and exposes the upper surfaces of the secondmetal plated layers 37 n, 37 p is formed.

Next, in a similar manner as in the removing growth substrate: S109, theforming fluorescent material layer: S110 and the singulating S: 414,removing growth substrate: S412, forming fluorescent material layer:S413 and singulating: S414 are respectively performed. Thus, a lightemitting device 100C as shown in FIG. 14A to FIG. 15B is completed.

As shown in the above, a semiconductor light emitting element and amethod of manufacturing the semiconductor light emitting element areillustrated in accordance with the embodiments for carrying out thepresent invention, but the scope of the invention is not limited to theabove description, and should be widely understood based on the scope ofclaim for patent. Further, based on the above description, it will beobvious that various changes and modifications can be made thereinwithout departing from the scope of the invention.

What is claimed is:
 1. A light emitting device comprising: asemiconductor light emitting element comprising: a semiconductor stackedlayer body including a p-type semiconductor layer and an n-typesemiconductor layer, a p-side electrode electrically connected to thep-type semiconductor layer and an n-side electrode electricallyconnected to the n-type semiconductor layer which are disposed at onesurface side of a surface side of the semiconductor stacked layer bodywith the p-type semiconductor layer or a surface side of thesemiconductor stacked layer body with the n-type semiconductor layer; aresin layer disposed on the one surface side of the semiconductorstacked layer body; an electrode for p-side external connection disposedexposed on a surface of the resin layer; an electrode for n-sideexternal connection disposed exposed on a surface of the resin layer; ap-side inner conductive member disposed in the resin layer andelectrically connecting the p-side electrode and the electrode forp-side external connection; and an n-side inner conductive memberdisposed in the resin layer and electrically connecting the n-sideelectrode and the electrode for n-side external connection; the p-sideinner conductive member and the n-side inner conductive memberrespectively include a first metal plated layer and a first metal wire,or a first metal plated layer and a first metal wire bump.
 2. The lightemitting device according to claim 1, wherein the p-side innerconductive member and the n-side inner conductive member respectivelyinclude the first metal wire bump, and the first metal wire bumpincludes a plurality of bumps.
 3. The light emitting device according toclaim 1, wherein the resin layer is a stacked layer of a first embeddedplating layer having the first metal plating embedded therein, and afirst wire embedded layer having the first wire bump embedded therein.4. The light emitting device according to claim 3, wherein the resinlayer further includes a second embedded plating layer, and the p-sideinner conductive member and the n-side inner conductive memberrespectively include the second metal plating.
 5. The light emittingdevice according to claim 2, wherein the resin layer further contains asecond wire embedding layer having a second metal wire of a second metalwire bump embedded therein, and the p-side inner conductive member andthe n-side inner conductive member respectively including a second metalwire or a second metal wire bump.
 6. The light emitting device accordingto claim 5, wherein the p-side inner conductive member and the n-sideinner conductive member respectively include the second metal wire bump,and the second metal wire bump includes a plurality of bumps.
 7. Thelight emitting device according to claim 1, wherein a surface of theresin layer to which the electrode for p-side external connection andthe electrode for n-side external connection are disposed is an oppositesurface from a surface facing the one surface side of the semiconductorstacked layer body.
 8. The light emitting device according to claim 1,wherein the first metal plated layer is joined to the p-side electrodeand the first metal plated layer is joined to the n-side electrode. 9.The light emitting device according to claim 8, wherein the first metalwires are connected to the first metal plated layer and at least one ofthe first wires has a wedge-shaped end portion in one end and isconnected to the first metal plated layer with the end portion.
 10. Thelight emitting device according to claim 1, wherein one of the firstmetal wire and the first metal wire bump is joined to the p-typeelectrode and one of the first metal wire and the first metal wire bumpis joined to the n-side electrode.
 11. The light emitting deviceaccording to claim 10, wherein the first metal wires are joined to thep-side electrode and the n-side electrode respectively and at least oneof the first metal wires has a wedge-shaped end portion in one end andis connected to one of the p-side electrode and the n-side electrodewith the end portion.
 12. The light emitting device according to claim1, wherein in the length direction of the resin layer, a wiring lengthof the first metal plated layer is longer than a wiring length of one ofthe first metal wire and the first metal wire bump.
 13. The lightemitting device according to claim 1 further comprising a wavelengthconverting layer disposed on the other surface side of the semiconductorstacked layer body and configured to convert light of a wavelengthemitted from the semiconductor light emitting element to light of adifferent wavelength.